Wheelchairs are an important means of transportation for a significant portion of society. Whether manual or powered, wheelchairs provide an important degree of independence for those they assist. However, this degree of independence can be limited if the wheelchair is required to traverse obstacles such as, for example, curbs that are commonly present at sidewalks, driveways, and other paved surface interfaces.
In this regard, most wheelchairs have front and/or rear casters to stabilize the chair from tipping forward or backward and to ensure that the drive wheels are always in contact with the ground. On such wheelchairs, the caster wheels are typically much smaller than the driving wheels and located forward and/or rear of the drive wheels. Though this configuration provides the wheelchair with greater stability, it makes it difficult for such wheelchairs to climb over obstacles such as, for example, curbs or the like, because the casters cannot be driven over the obstacle due to their small size and general inability to become vertically misaligned with the drive wheel level or with the level of an associated caster wheel.
The Applicant has recognised the need for a wheelchair of the type having drive wheels and suspended front and/or rear caster wheels having improved stability particularly when traversing over uneven ground or obstacles. The Applicant has further recognised the need for improving rigidity and strength in the overall wheelchair structure while maintaining the wheelchair's ability to accommodate essential components including a caster wheel assembly, battery box and other components that may be necessary to drive the wheelchair.
Any discussion of documents, acts, materials, devices, articles or the like, which has been included in the present specification is solely for the purpose of providing a context for the present invention. It should not be taken as an admission that any or all of the previous discussion forms part of the prior art base or was common general knowledge in the field of the invention as it existed before the priority date of any of the claims herein.